Evaluating the presence of radium-226 in soil surrounding a coal-fired power plant using the multi-agency radiation survey and site investigation manual (MARSSIM) PublicDeposited

Descriptions

Coal-fired power plants constitute a significant source of energy production for the United States, and are projected to do so for decades to come. Most of the scrutiny coal-fired power plants receive is in the form of environmental concerns regarding green house gas emissions of carbon dioxide, sulfur dioxide, and others. It is known that coal fly ash released through the stacks of coal power plants contains concentrated levels of naturally-occurring radiation, such as Radium-226. However, since the source of radiation is natural and the activity levels are low, there are no nuclear regulatory requirements imposed on coal plants.
The focus of this study was to use the Nuclear Regulatory Commission’s (NRC) facility release criteria to determine whether the concentration of naturally occurring Radium-226 present in soil surrounding the Centralia Power Plant is elevated relative to soil collected 80 kilometers away.
The non-parametric Wilcoxon Rank Sum test was used to compare twenty-eight soil samples collected within 3.4 kilometers of the Centralia Power Plant stacks against an equal number of reference samples collected in Port Orchard, Washington. It was determined that the average concentration of Radium-226 in soil near the power plant was 1.59 pCi/g, while the average concentration in reference soil was 0.59 pCi/g. The study suggests that the area around the power plant would fail to pass the release criteria of a NRC Multi-Agency Radiation Survey and Site Investigation (MARSSIM) Class 3 survey unit. If it is true that coal fired power plants increase background radiation levels measurably, but not at a level sufficient to cause alarm, it may be sensible to revise the strict emissions standards for nuclear facilities or increase requirements for utilities other than nuclear.